I've got OpenWrt setup on a Raspberry Pi 5 with 3 Ethernet interfaces (2 USB), but I need a setup with advanced routing between them and I don't know how to configure it.
- eth0 is for downstream LAN (there is a switch plugged in)
- eth1 is for a WAN, but only for internet access
- eth2 is for another WAN, but only for accessing the LAN on this WAN
So, on eth2 is another router that I want to be able to communicate with devices on its LAN, but not allow connection to this router's internet. Instead, internet should come from eth1. Devices on eth0 should be able to connect to LAN devices on the router connected to eth2, and vice versa.